Morphology

Morphology

Colonies form extensive, lacey sheets on algal substrates. Zooids are rectangular with tubercules (spines) protruding from the corners. The lateral walls of the zooids are calcified, but incorporate two vertical uncalcified bands which provide flexibility to colony as the aglal substrate moves in the waves. Large chitonous spines are produced rapidly in response to waterborne cues from the trophically specialised nudibranch, Doridella steinberae.